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71.
郭瑞璜 《消防技术与产品信息》2005,(9):74-76
日本消防研究所山田常圭博士,从事消防科研20余年,取得了多项成果,荣获2004年度日本火灾学会奖。其科研概况如下:1疏散对策的研究疏散行为和疏散诱导研究主要内容是:1)火灾烟雾刺激对视认性的影响;2)在充满烟雾的走廊里,人在心理上的不安全感;3)关于安全出口指示灯容易辨认性评价;4)通过自愿者现场试验,探讨闪烁移动型光源的疏散诱导效果等。这些都属于“烟雾中逃生行为的可能性”专题。这个专题荣获1997年国际火灾安全科学会颁发的Emmons奖。在进行实验研究时,使用了一些独特的方法,如研究烟雾刺激性对视认距离下降的影响时,让操作人员戴… 相似文献
72.
Thin sections cut from cast concrete cylinders have been examined in transmitted light to investigate the significance of coarse aggregate type in “primary” microfracturing. Concretes manufactured with crushed-rock aggregates and gravel aggregates were studied and, in every case, the dominant fracture type was a parting of the aggregate-matrix bond. Bond cracking was least severe with the marble aggregate where epitaxial calcite over-growth was indicated. The ability of bond cracks to maintain continuity by bridging surface irregularities, via mortar cracks, reduced the inhibiting influence of rough-surfaced aggregate on bond-crack development. 相似文献
73.
74.
Results are presented for experimental investigations on the traffic-induced oscillations of two full-scale foundations of a metallic tunnel, one of which is installed directly on the ground, and the other on cast-in-place piles. The foundations are close to one another with respect to mass and the load applied to them. Differences are revealed between the parameters of the actual oscillations of these foundations and their computed values. 相似文献
75.
D. K. C. WU CChem MRSC H. C. LAI BSc MPhil CChem MRSC K. W. LAW BSc CChem MRSC W. C. WONG BSc CEng MIMechE MHKIE 《Water and Environment Journal》1995,9(1):82-91
In order to protect the sensitive waters in Tolo harbour (Hong Kong), Sha Tin and Tai Po sewage-treatment works were first designed to remove 70% of the nitrogen load from the sewage. Since then, due to continuing serious eutrophication problems in the harbour, both plants have been modified to increase the removal efficiency to 90%.
The modifications were based on the Bardenpho process. However, the designers of the two plants adopted different approaches to process intensity, complexity and control of bacterial foam. At Sha Tin, the average monthly results have shown an increase of total nitrogen removal from 60–70% to about 80% since its completion. The addition of methanol was found to be ineffective on further enhancement of the denitrification rate due to difficulties in the apportioning of the second anoxic zone. The overall monthly results for Tai Po have also shown an increase in the removal rate to about 80%, even though 90% was achieved for a short period of time. The major problem encountered at the latter plant was that the process design did not provide an effective control on bacterial foaming, which had affected the smooth operation of the process. 相似文献
The modifications were based on the Bardenpho process. However, the designers of the two plants adopted different approaches to process intensity, complexity and control of bacterial foam. At Sha Tin, the average monthly results have shown an increase of total nitrogen removal from 60–70% to about 80% since its completion. The addition of methanol was found to be ineffective on further enhancement of the denitrification rate due to difficulties in the apportioning of the second anoxic zone. The overall monthly results for Tai Po have also shown an increase in the removal rate to about 80%, even though 90% was achieved for a short period of time. The major problem encountered at the latter plant was that the process design did not provide an effective control on bacterial foaming, which had affected the smooth operation of the process. 相似文献
76.
77.
Conclusions 1. The scheme that we developed is efficient and ensures thawing over a period of 40–45 days.
2. To accelerate thawing by 8–10 days when using two electric heaters in each hole, it is necessary to raise the heaters by
3–4 m after 25 days and continue thawing.
3. An 8–10-day reduction in the thaw time is also possible by using three 1.25-kW electric heaters in each hole in place of
two heaters of the same capacity, installing them at depths of 20, 14, and 8 m from the surface.
Taking the results of the experimental work account, the State Institute for Special Design developed a plan for the production
preconstruction thawing of soils over a area of 12,380 m2.
The volume of soil thawed was 324,400 m3.
Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 3, pp. 7–8. May–June, 1982. 相似文献
78.
不容置疑,技术落后是我国面临的问题,但管理落后却是更加紧迫的问题。作者通过对借用国外贷款项目的实地调研,从项目层面较微观的角度,分析总结了我国借用国外贷款项目管理中存在的突出问题。分别从项目法人责任制的落实、项目管理机构的设定、国内外两套资金的使用、项目实施阶段的更改、监督机构的完善、项目的可持续性、外债使用的效益和项目完成后的总结评价等几个方面进行了分析,同时,给出了相应的解决问题的对策。 相似文献
79.
Hybrid reactor for priority pollutant-trichloroethylene removal 总被引:3,自引:0,他引:3
The present study was initiated to explore the potential of a hybrid biological reactor, combining trickling filter (TF) and activated sludge process (ASP), to treat wastewater containing trichloroethylene (TCE) at ambient temperature at different hydraulic retention time (HRT). The biofilm acclimation was achieved in 55-60 days with gradual increase in TCE concentration from 1 mg/l to 100 mg/l with a parallel increase in the concentration of substrate sodium acetate and other nutrients. COD and TCE concentration were taken as prime parameters for monitoring the growth of biofilm. During acclimation COD removal varied between 54.6-97.5% while TCE was removed 72.6-99.9%. HRT study was performed after acclimation. The removal efficiency increased with decreasing flow rate with maximum TCE removal (99.99%) at 6 l/d corresponding to an HRT of 28 h (TF 18 h + ASP 10 h). This was followed by a C:N:P ratio study. A ratio of 100:20:1 led to the sustenance of maximum TCE removal. Maximum TCE removal (99.99%) was observed at a substrate:cosubstrate ratio of 100:1. A pH of 7.4 +/- 0.2 was found to be optimum for degradation. Finally, volatilization losses were estimated to be 18.5%. A mass balance gave an efficiency of 81.51% for biological removal of TCE. 相似文献
80.
The paper provides an overview of three software for structural reliability analysis developed at the University of California, Berkeley. These are CalREL, which is a general-purpose structural reliability code written in FORTRAN; FERUM, which is a collection of Matlab® files that can be used for structural reliability analysis in conjunction with simple finite element models; and OpenSees, which is an object-oriented code for nonlinear structural response simulation with reliability capabilities. Reliability analysis methods featured by these software include FORM, SORM, Monte Carlo simulation, and various importance sampling methods. In addition, variable importance and sensitivity measures are provided. 相似文献